Joseph Devenney/Getty Images(MIDLAND, Texas) -- Four people died and 17 others were injured when a freight train plowed into a parade float carrying wounded veterans at a crossing in Midland, Texas.

The float was one of two flatbed tractor-trailers carrying wounded veterans and their families to an honorary banquet during Show of Support's Hunt for Heroes parade Thursday afternoon. A Union Pacific train approached after 4:30 p.m. local time just as the parade was crossing the tracks, striking the vehicle, according to officials and witnesses.

Two people died at the scene and two others died at Midland Memorial Hospital, Midland Police Chief Price Robinson said. Seventeen people in all were transported to the hospital and 10 were treated and released. Four people were in stable condition and one is in critical condition as of Friday morning.

Joshua Michael, 34, was killed in the crash but was able to save his wife, his mother-in-law told the Amarillo Globe-News.

"He pushed his wife off the float -- my daughter," Mary Hefley told the newspaper. "He was that kind of guy. He always had a smile on his face. He would do for others before he would do for himself."

Hefley said Michael retired from the Army due to health reasons.

About two dozen veterans and their spouses had been sitting in chairs on the back of a flatbed tractor-trailer decorated with American flags and signs identifying each veteran.

The first truck crossed the tracks in time, but the second did not, according to Hamid Vatankhah, a witness who owns a used car lot near the scene of the crash.

Sirens from the police cars in the parade may have drowned out the sound of the approaching train, Vatankhah said.

The impact, witnesses say, was deafening as the train struck the parade float. "Some people were able to jump, and some that were sitting in wheelchairs on top couldn't do nothing about it," Vatankhah added.

Union Pacific spokesman Tom Lange said it appeared safety devices at the crash site were working. However, there were conflicting reports by eyewitnesses about whether the gates went down at the crossing when the train approached.

"I saw the truck crossing the tracks. About halfway across the gates started coming down. The truck tried to blow his horn to get the other people in front of him out of the way. The gates actually hit the first people on the trailer," witness Michael Briggs said.

"Our preliminary findings indicate that the lights and gates were working at the time of the incident and that our train crew sounded the locomotive horn," said Lange.

The National Transportation Safety Board was at the scene and has launched an investigation into the accident.